Broken Bones

 

Overview

The human skeletal system is designed to support the human body, offer it protection, and provide a means of locomotion. Bone is the essential framework to which muscles are attached. Bone is constructed in layers. The outside layer is known as the periosteum. This is where blood vessels and nerve cells are located. The next layer is the compact bone. This area has collagen and crystals of calcium and phosphorus. The next layer is of spongy bone, with shock-absorber qualities. Then the medullary cavity, filled with marrow , forms the inside of the bone. This layered-tube architecture allows the bone its compressional strength , while keeping it very light. However, forces on bones are not always compressional. Lateral forces, twisting stresses, and powerful impacts may cause the bone to break, or fracture. There are two types of fractures: closed and open. A closed fracture occurs when the skin is not broken. An open fracture is when the skin has been broken and involves an open wound. This type of fracture is more serious because of the increased risk of infection and shock caused by blood loss and damaged tissue. Keeping the broken body part stationary -- immobilizing it -- will stabilize the injured area and prevent the bones from shifting until further treatment is available. Splints are used to immobilize an area. They can be made from cardboard, newspapers, sticks, or any other rigid material. When a cast is needed, the doctor first checks that the bones are in correct alignment to promote proper healing. A cast is then placed over the fractured area to immobilize it, allowing the bones to grow back and heal in the desired configuration. Although fractures are an unfortunate occurrence, most of us can take precautions to avoid them. There are certain diseases, however, that make some people more susceptible to fractures. Diseases of the bone, including osteoporosis , rickets , and osteoarthritis can cause bone deterioration or fragility. This can increase the likelihood or severity of a bone fracture.

Activity

Why is it important to immobilize a fractured bone? Observe how to splint a fractured limb, and learn the importance of immobilization in the treatment of broken bones. You will also experience the sensation of limited movement created by a splint or a cast. Materials

• Red Cross First Aid Workbook OR another guide on splinting broken bones
• cardboard for splints
• triangular bandages made from torn sheets or fabric scraps
• newspapers
• padding for splinting
• any other type of material that can be used for splinting

1. Review the first-aid resources for information and diagrams on how to splint arms, legs, and fingers.
2. Demonstrate the proper procedures for splinting an arm.
3. Pair up and practice splinting each other. Try using different materials to splint the arm.
4. When the arm splint is completed, repeat steps 2 and 3 for the leg splint and the finger splint.

Resources

American Red Cross standard first aid workbook. (1988) Washington, DC:
American Red Cross.
Gray, H. (1901, 1977) Gray's anatomy. New York: Bounty Books.
Kapit, W., and L. Elson. (1977) The anatomy coloring book. New York: Harper
Collins.
Community resources:
American Red Cross chapter
School nurse
Emergency-response units
Hospitals or emergency-treatment centers

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